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101.
Tomotaka Tanaka Hiroshi Yamagami Masafumi Ihara Rie Motoyama Kazuki Fukuma Tetsuya Miyagi Kazutaka Nishimura Kazunori Toyoda Kazuyuki Nagatsuka 《PloS one》2015,10(8)
Background
Seizure is a common complication after stroke (termed “post-stroke seizure,” PSS). Although many studies have assessed outcomes and risk factors of PSS, no reliable predictors are currently available to determine PSS recurrence. We compared baseline clinical characteristics and post-stroke treatment regimens between recurrent and non-recurrent PSS patients to identify factors predictive of recurrence.Methods
Consecutive PSS patients admitted to our stroke center between January 2011 and July 2013 were monitored until February 2014 (median 357 days; IQR, 160–552) and retrospectively evaluated for baseline clinical characteristics and PSS recurrence. Cumulative recurrence rates at 90, 180, and 360 days post-stroke were estimated by Kaplan—Meier analysis. Independent predictors of recurrent PSS were identified by Cox proportional-hazards analysis.Results
A total of 104 patients (71 men; mean age, 72.1 ± 11.2 years) were analyzed. PSS recurred in 31 patients (30%) during the follow-up. Factors significantly associated with PSS recurrence by log-rank analysis included previous PSS, valproic acid (VPA) monotherapy, polytherapy with antiepileptic drugs (AEDs), frontal cortical lesion, and higher modified Rankin Scale score at discharge (all p < 0.05). Independent predictors of recurrent PSS were age <74 years (HR 2.38, 95% CI 1.02–5.90), VPA monotherapy (HR 3.86, 95% CI 1.30–12.62), and convulsions on admission (HR 3.87, 95% CI 1.35–12.76).Conclusions
Approximately one-third of PSS patients experienced seizure recurrence within one year. The predictors of recurrent PSS were younger age, presence of convulsions and VPA monotherapy. Our findings should be interpreted cautiously in countries where monotherapy with second-generation AEDs has been approved because this study was conducted while second-generation AEDs had not been officially approved for monotherapy in Japan. 相似文献102.
Xia Jiang Tatsuo Kanda Shingo Nakamoto Tatsuo Miyamura Shuang Wu Osamu Yokosuka 《Experimental cell research》2014
Previous studies demonstrated that androgen receptor (AR) is expressed in human hepatocellular carcinoma (HCC), one of the male-dominant diseases. Glucose-regulated protein 78 kDa (GRP78/Bip), which has a role in cancer development, is one of the androgen response genes in prostate cell lines. The aim of this study was to investigate the impact of AR on endoplasmic reticulum (ER)-stress signaling in human hepatoma. AR and GRP78 expressions were examined in human liver tissue panels. Human hepatoma cells stably expressing short hairpin RNA targeting AR and cells over-expressing AR were generated. The expressions of ER-stress molecules and AR were measured by real-time RT-PCR and Western blotting. The effect of AR on ER-stress responsive gene expression was examined by reporter assay. Strong positive correlation between AR mRNA and GRP78 mRNA was observed in stage I/II-HCCs. AR enhanced ER-stress responsive element activities and GRP78 expression, and regulated ER-stress response in hepatocytes. Sorafenib strongly induced significant apoptosis in HepG2 cells by the inhibition of AR and inhibition of the downstream GRP78. AR seems a co-regulator of GRP78 especially in earlier-stage HCC. AR plays a critical role in controlling ER-stress, providing new therapeutic options against HCC. 相似文献
103.
104.
Haruko Ando Hiroko Ogawa Shingo Kaneko Hajime Takano Shin‐Ichi Seki Hajime Suzuki Kazuo Horikoshi Yuji Isagi 《Ibis》2014,156(1):153-164
The Red‐headed Wood Pigeon Columba janthina nitens is endemic to the Ogasawara Islands, an oceanic island chain located 1000 km south of the main islands of Japan. The subspecies is at high risk of extinction because of its small population size and restricted habitat range. We undertook genetic analyses of this pigeon using sequences of a portion of the mitochondrial control region and five microsatellite markers to estimate the genetic characteristics of two wild populations from the Bonin and Volcano Islands, as well as one captive breeding population. The genetic diversity of the wild individuals was exceptionally low in both the mitochondria (nucleotide diversity = 0.00105) and at the microsatellite (3.2 alleles per locus and HE = 0.12) loci. Higher numbers of microsatellite genotypes were observed in the Volcano Islands population than in the Bonin Islands population, which may be because of the relatively low impact of human disturbance. The most common mitochondrial haplotypes and microsatellite alleles observed in the two wild populations were completely fixed in the captive population. Our results suggest that the genetic diversity of the captive population needs to be increased. However, introduction of a wild individual into a captive population can lead to a decreased genetic diversity in the wild population and therefore should be done with caution. The genetic differentiation between the Bonin and the Volcano island groups was low, and the populations of the two island groups should be regarded as a single evolutionarily significant unit. However, special consideration is required for habitat conservation in the Volcano Islands, which may be functioning as a sanctuary for the Red‐headed Wood Pigeon. For the long‐term conservation of threatened bird species that live on remote oceanic islands, determination of management units considering gene flow caused by their flying capacity and maintenance of genetically suitable wild and captive populations are essential. 相似文献
105.
Shingo Izawa Kayo Ikeda Takeo Miki Yoshinori Wakai Yoshiharu Inoue 《Applied microbiology and biotechnology》2010,88(1):277-282
Although ethanol and osmotic stress affect the vacuolar morphology of Saccharomyces cerevisiae, little information is available about changes in vacuolar morphology during the processes of wine making and Japanese sake (rice wine) brewing. Here, we elucidated changes in the morphology of yeast vacuoles using Zrc1p-GFP, a vacuolar membrane
protein, so as to better understand yeast physiology during the brewing process. Wine yeast cells (OC-2 and EC1118) contained
highly fragmented vacuoles in the sake mash (moromi) as well as in the grape must. Although sake yeast cells (Kyokai no. 9 and no. 10) also contained highly fragmented vacuoles during the wine-making process, they showed quite a distinct
vacuolar morphology during sake brewing. Since the environment surrounding sake yeast cells in the sake mash did not differ much from that surrounding wine yeast cells, the difference in vacuolar morphology during sake brewing between wine yeast and sake yeast was likely caused by innate characters. 相似文献
106.
Osami Shoji Takashi Fujishiro Shingo Nagano Shota Tanaka Takuya Hirose Yoshitsugu Shiro Yoshihito Watanabe 《Journal of biological inorganic chemistry》2010,15(8):1331-1339
Cytochrome P450BSβ, a H2O2-dependent cytochrome P450 catalyzing the hydroxylation of long-alkyl-chain fatty acids, lacks the general acid–base residue
around the heme, which is indispensable for the efficient generation of the active species using H2O2. On the basis of the crystal structure of the palmitic acid bound form of cytochrome P450BSβ, it was suggested that the role of the general acid–base function was provided by the carboxylate group of fatty acids. The
participation of the carboxylate group of the substrate was supported by the fact that cytochrome P450BSβ can catalyze oxidations of nonnatural substrates such as styrene and ethylbenzene in the presence of a series of short-alkyl-chain
carboxylic acids as a dummy molecule of fatty acid. We refer to a series of short-alkyl-chain carboxylic acids as a “decoy
molecule”. As shown here, we have clarified the crystal structure of the decoy-molecule-bound form and elucidated that the
location of its carboxylate group is virtually the same as that of palmitic acid in the heme cavity, indicating that the carboxylate
group of the decoy molecule serves as the general acid–base catalyst. This result further confirms that the role of the acid–base
function is satisfied by the carboxylate group of the substrates. In addition, the structure analysis of the substrate-free
form has clarified that no remarkable structural change is induced by the binding of the decoy molecule as well as fatty acid.
Consequently, whether the carboxylate group is positioned in the active site provides the switching mechanism of the catalytic
cycle of cytochrome P450BSβ. 相似文献
107.
Shingo Nakajima Tohru Hira Yuzuru Eto Kozo Asano Hiroshi Hara 《Regulatory peptides》2010,159(1-3):148-155
We previously demonstrated that intraduodenal administration of an arginine-rich β51–63 peptide in soybean β-conglycinin suppresses food intake via cholecystokinin (CCK) secretion in rats. However, the cellular mechanisms by which the β51–63 peptide induces CCK secretion remain to be clarified. In the present study, we examined whether the extracellular calcium-sensing receptor (CaR) mediates β51–63-induced CCK secretion in murine CCK-producing enteroendocrine cell line STC-1. CCK secretion and changes in intracellular Ca2+ concentration in response to β51–63 peptide were measured in STC-1 cells under various extracellular Ca2+ concentrations and after treatment with a CaR antagonist. Intracellular Ca2+ concentrations in response to β51–63 peptide and extracellular Ca2+ were also measured in CaR-expressing human embryonic kidney (HEK-293) cells. The β51-63 peptide induced CCK secretion and intracellular Ca2+ mobilization in STC-1 cells under normal (1.2 mM) extracellular Ca2+ conditions in a dose-dependent manner. These responses to β51–63 peptide were reduced by the removal of intra- or extracellular Ca2+ but enhanced by increasing extracellular Ca2+ concentrations. Intracellular Ca2+ mobilization induced by extracellular Ca2+ was also increased by the pretreatment with β51–63 peptide. Treatment with a specific CaR antagonist (NPS2143) inhibited β51–63-induced CCK secretion and intracellular Ca2+ mobilization. In addition, HEK-293 cells transfected with CaR acquired sensitivity to the β51–63 peptide. From these results, we conclude that CaR is the β51–63 peptide sensor responsible for the stimulation of CCK secretion in enteroendocrine STC-1 cells. 相似文献
108.
Shunsuke Ohashi Tatsuya Iemura Naoki Okada Shingo Itoh Hayato Furukawa Masaaki Okuda Mayumi Ohnishi-Kameyama Takuro Ogawa Hideaki Miyashita Tadashi Watanabe Shigeru Itoh Hirozo Oh-oka Kazuhito Inoue Masami Kobayashi 《Photosynthesis research》2010,104(2-3):305-319
Minor but key chlorophylls (Chls) and quinones in photosystem (PS) I-type reaction centers (RCs) are overviewed in regard to their molecular structures. In the PS I-type RCs, the prime-type chlorophylls, namely, bacteriochlorophyll (BChl) a′ in green sulfur bacteria, BChl g′ in heliobacteria, Chl a′ in Chl a-type PS I, and Chl d′ in Chl d-type PS I, function as the special pairs, either as homodimers, (BChl a′)2 and (BChl g′)2 in anoxygenic organisms, or heterodimers, Chl a/a′ and Chl d/d′ in oxygenic photosynthesis. Conversions of BChl g to Chl a and Chl a to Chl d take place spontaneously under mild condition in vitro. The primary electron acceptors, A 0, are Chl a-derivatives even in anoxygenic PS I-type RCs. The secondary electron acceptors are naphthoquinones, whereas the side chains may have been modified after the birth of cyanobacteria, leading to succession from menaquinone to phylloquinone in oxygenic PS I. 相似文献
109.
Hiroshi Furuta Yuudai Kondo Shingo Nakahata Sumio Sakoda 《Biochemical and biophysical research communications》2010,391(4):1785-1791
Oral cancer is one of the most common cancers worldwide, and squamous-cell carcinoma (OSCC) is the most common phenotype of oral cancer. Although patients with OSCC have poor survival rates and a high incidence of metastasis, the molecular mechanisms of OSCC development have not yet been elucidated. This study investigated whether N-myc downstream-regulated gene 2 (NDRG2) contributes to the carcinogenesis of OSCC, as NDRG2 is reported to be a candidate tumor-suppressor gene in a wide variety of cancers. The down-regulation of NDRG2 mRNA, which was dependent on promoter methylation, was seen in the majority of OSCC cases and in several cases of precancerous leukoplakia with dysplasia. Induction of NDRG2 expression in an HSC-3/OSCC cell line significantly inhibited cell proliferation and decreased colony formation ability on soft agar. The majority of OSCC cell lines showed an activation of PI3K/Akt signaling, and enforced expression of NDRG2 in HSC-3 cells decreased the level of phosphorylated Akt at Serine 473 (p-Akt). Immunohistochemical p-Akt staining was detected in 56.5% of the OSCC tumors, and 80.4% of the tumors were negative for NDRG2 staining. Moreover, positive p-Akt staining was inversely correlated with decreased NDRG2 expression in OSCC tumors with moderate to poor differentiation (p < 0.005). Therefore, NDRG2 is a candidate tumor-suppressor gene for OSCC development and probably contributes to the tumorigenesis of OSCC partly via the modulation of Akt signaling. 相似文献